Follow-up from "Revamp Merge Request documentation"

The following discussions from !18644 (merged) should be addressed:

• @eread started a discussion: (+1 comment)

  This is a golden opportunity to refactor that screenshot. Even just to break it down into components.

• @rdickenson started a discussion: (+1 comment)

  @marcel.amirault - This is definitely an improvement over the current MRs page. I like the addition of the tables, and that the page is much smaller than previously.

  I have some questions and suggestions on the changes. I think this MR could be accepted as it is now, but also that it's worth considering some questions.

  • Why are the feature tables not located within the separate pages - creating an MR, and reviewing an MR?
    • Because their information is specific to those "stages" of an MR, I think it would be most useful to have the tables co-located with their relevant docs.
  • Why is the View changes between file versions section in the Creating merge requests page?
    • I would think that would be located with the Reviewing MRs docs.
  • As we discussed recently, I think it would be useful to present a simplified workflow diagram representing the lifecycle of an MR.
    • Each stage of the lifecycle could represent a section of the docs. I think that would help guide the reader to the appropriate documentation. Note: This suggestion is very much a matter of personal opinion. I believe it would be a useful addition to this MR, but it should be dealt with in a separate MR.